Merge branch 'master' into nataled-patch-13

Author: nataled

principles/fp-001-open.md

@@ -61,8 +61,7 @@ The attribution method for individual terms reused in another ontology (e.g., by
 1. **In OWL** - Any ontology re-using individual terms from another ontology should:
 
    1. re-use the original term IRI (which for OBO Foundry ontologies is generally in the form of an OBO Foundry PURL)
-   2. use an IAO:imported from annotation <http://purl.obolibrary.org/obo/IAO_0000412> on each imported term to link back to the group (i.e. ontology) maintaining it, where more information would be available about the license
-   3. include any annotations for term or definition editors from the original ontology
+   2. include any annotations for term or definition editors from the original ontology
 
 2. **In OBO** - Any ontology re-using individual terms from another ontology should:
    1. re-use the original term ID (of the form <GO:0000001>)
@@ -124,31 +123,6 @@ The first course of action should be to reuse the external term as is, by import
 
 Please see the discussion tab for additional discussion of how to use different annotation properties to credit external ontologies or definition sources.
 
-#### Example 3A: IAO:imported from
-
-The Ontology for Biomedical Investigation (OBI) imports the class "environmental material" from the Environment Ontology (ENVO), using OntoFox. The imported from axiom is automatically generated by Ontofox and added to "environmental material" in OBI:
-
-```
-<!-- <http://purl.obolibrary.org/obo/ENVO_00010483> -->
-
-<owl:Class rdf:about="&obo;ENVO_00010483">
-
-<rdfs:label rdf:datatype="&xsd;string">environmental
-material</rdfs:label>
-
-<rdfs:subClassOf rdf:resource="&obo;BFO_0000040"/>
-
-<obo:IAO_0000115 rdf:datatype="&xsd;string">Material in or on which
-organisms may live.</obo:IAO_0000115>
-
-<obo:IAO_0000111 rdf:datatype="&xsd;string">environmental
-material</obo:IAO_0000111>
-
-<obo:IAO_0000412 rdf:resource="&obo;envo.owl"/>
-
-</owl:Class>
-```
-
 ## Counter-Examples
 
 - An ontology with no license statement is by default subject to the most restrictive copyright laws for those parts of the ontology that are copyrightable, and therefore is not useful within the OBO Foundry.

principles/fp-002-format.md

@@ -15,7 +15,7 @@ A common format allows the maximum number of people to access and reuse an ontol
 
 ## Recommendations and Requirements
 
-All ontologies MUST have at least one OWL product whose name corresponds to the registered prefix (e.g., 'GO' --> go.owl, 'OBI' --> obi.owl). Thus the ontology whose IRI is http://purl.obolibrary.org/obo/ro.owl (known to the OBO Foundry as 'RO'), must have at least the product ro.owl. Developers are free to use whatever combination of technologies and formats is appropriate for development. However, the official OWL PURL (see [Principle 3](https://obofoundry.org/principles/fp-003-uris.html)) for the ontology MUST resolve to a syntactically valid OWL file using the [RDF-XML](https://www.w3.org/TR/rdf-syntax-grammar/) syntax.
+All ontologies MUST have at least one OWL product whose name corresponds to the registered prefix (e.g., 'GO' --> go.owl, 'OBI' --> obi.owl). Thus the ontology whose IRI is http://purl.obolibrary.org/obo/ro.owl (known to the OBO Foundry as 'RO'), MUST have at least the product ro.owl which MUST be a syntactically valid OWL file using the [RDF-XML](https://www.w3.org/TR/rdf-syntax-grammar/) syntax. Developers are free to use whatever combination of technologies and formats is appropriate for development.
 
 Developers can OPTIONALLY produce ontologies in other formats. These are conventionally the same IRI as the owl, but with .owl changed to the relevant extension (e.g., '.obo', '.json'). Note that such products are not listed by default. If you produce an additional format product, you should register it under the 'products' field in the appropriate metadata file found in this [folder](https://github.com/OBOFoundry/OBOFoundry.github.io/tree/master/ontology).
 

principles/fp-003-uris.md

@@ -17,6 +17,8 @@ A unique namespace within the OBO Foundry Library allows the source of an elemen
 
 Each ontology MUST have a unique IRI in the form of an OBO Foundry permanent URL (PURL). The PURL must include the ontology namespace, which is a short string of letters (usually 2-5) that represents the ontology. Namespaces MUST be approved by the OBO Foundry Operations Committee. Every element (class, property, etc.) created by the ontology MUST use the namespace in the identifier of each element, as specified in the OBO Foundry [ID policy](http://www.obofoundry.org/id-policy).
 
+The official PURL for the ontology, after redirection, MUST resolve to the ontology OWL file (see [Principle 2](https://obofoundry.org/principles/fp-002-format.html) for format requirements). Furthermore, PURLs for individual terms, after redirection, MUST resolve to a dedicated _term-centric_ destination page containing the appropriate content.
+
 ## Implementation
 
 ### Ontology Namespace: